Page 7 - EUREKA! Summer 2018

Image courtesy Dr. James Heilman

Fine-tuning cancer care

bout half of all cancer patients — and 20 percent
of all Canadians — will get radiation therapy as part
Aof their medical care. These statistics, and the fact
that radiation damages healthy cells while destroying
cancer cells, speaks to the need to develop more precise
approaches to cancer treatment. Brachytherapy, which
entails implanting small radioactive sources roughly the
Go green targeted, has been evolving as a technique for more than a
size of a grain of rice (pictured above) near the area being

century, with medical physicists such as Carleton professor
Rowan Thomson working to help refine the treatment.
The standard protocol for brachytherapy begins with
Gauging the health benefits deciding where to position the radioactive sources, either
high-dose temporary implants or low-dose and permanent.
Afterward, a CT scan is done to determine the actual
of getting active in urban nature source locations; this information is used to calculate
Photo: Richard Hinchcliff of the treatment. Thomson and her collaborators at the
doses, and further analyses evaluates the effectiveness

Ottawa Medical Physics Institute are part of an effort to
come up with more accurate dose calculation algorithms —
using Monte Carlo or probability simulations — and she is
also a member of a task force that’s developing guidelines
for bringing these ideas from the research stage to clinical
practice.
here is evidence of several health benefits associated behaviours that increase the risk of chronic disease.” used Ottawa area bike paths. One of Thomson’s current projects revolves around “egs
with neighbourhood greenness, but reasons for this The preceding text is taken from a paper published last “Greenness in urban areas has been linked to a number brachy,” an open-source code for rapid brachytherapy
Tare unclear. Studies have found that those who live year in the journal Environmental Research by Carleton of healthy behaviours, including reduced obesity and dose calculations (“egs” is short for electron gamma
in greener neighbourhoods are more physically active, and Health Sciences professor Paul Villeneuve, an epidemiologist increased participation in physical activity, and facilitates shower) developed at Carleton. It’s currently being tested
have lower rates of obesity. Relatively few studies have and biostatistician cross-appointed to the School of social interaction that come with its own health benefits,” on 40 patients in Kelowna, B.C., where brachytherapy is
attempted to characterize associations between greenness Mathematics and Statistics. Villeneuve and his students have Villeneuve wrote in an email to the Ottawa Citizen. common because many cancer patients in the region live
and both obesity and physical activity concurrently, or also done research showing that the four square kilometres “Greenness in urban areas has also been linked to a in remote locations and cannot easily come to the city
among women who are at higher risk of developing cancer of green space in Ottawa’s Central Experiment Farm — number of important health outcomes including improved for treatment. “Medical doctors prescribe radiation as
and for whom physical activity may be important for where the accompanying photo was taken — improves air sleep quality, reduced stress and lower mortality. These a treatment,” says Thomson, Canada Research Chair in
primary prevention…. Our findings indicate that, amongst quality, reduces pollution and lowers temperatures in the effects have been observed in both affluent and low- Radiotherapy Physics, “and medical physicists study the
U.S. adult women at higher risks of breast cancer, residential surrounding area. This summer, they will begin mapping air income neighbourhoods.” interaction of radiation and matter so we can improve the
proximity to greenness may help mitigate against sedentary pollution, noise and temperature measures along commonly care patients receive.”

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